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        h1{
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            font-size: 30px;;
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      p{
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<body>
  
    <p><img id="s" src="123.png"></p>
    
    <br>
    <div id="a"  >
        <h1>
            拳击游戏
        </h1>
        <br><br><br><br><br><br><br><br>
        <p>
            玩家： <input type="text" name="name"><br><br>
            性别：<label><input type="radio" name="graden" value="1">男</label>&nbsp;
                <label><input type="radio" name="graden" value="2">女</label><br><br>
            等级：<select name="degree" >
                <option value="">----请选择----</option>
                <option value="1">青铜</option>
                <option value="2">白银</option>
                <option value="3">黄金</option>
                <option value="4">铂金</option>
            </select>  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <input type="button" value="进入游戏">  <input type="button" value="关闭游戏">
        </p>
     </div> 
   

     <div  class="cls">
        kkkk
     </div><br>
     <div  class="cls">
        cccc
     </div>
</body>

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